Let $W_i$ be the null space of $(T-c_i I)$. If $T$ is diagonalizable, then prove that $sum_i dim(W_i) = dim...












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Let $T$ be a linear operator on a finite dimensional vector space $V$ and let $c_1,c_2ldots ,c_k$ be the distinct eigenvalues of T. Let $W_i$ be the null space of $(T-c_i I)$. If $T$ is diagonalizable, then prove that $$sum_i dim(W_i) = dim(V)$$




I am unable to connect things in order to logically think about this. How do I go about proving this?










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  • $begingroup$
    See proposition $5.21$ on page no:$101$ in this book!
    $endgroup$
    – Chinnapparaj R
    Jan 29 at 7:36


















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$begingroup$



Let $T$ be a linear operator on a finite dimensional vector space $V$ and let $c_1,c_2ldots ,c_k$ be the distinct eigenvalues of T. Let $W_i$ be the null space of $(T-c_i I)$. If $T$ is diagonalizable, then prove that $$sum_i dim(W_i) = dim(V)$$




I am unable to connect things in order to logically think about this. How do I go about proving this?










share|cite|improve this question











$endgroup$












  • $begingroup$
    See proposition $5.21$ on page no:$101$ in this book!
    $endgroup$
    – Chinnapparaj R
    Jan 29 at 7:36
















1












1








1





$begingroup$



Let $T$ be a linear operator on a finite dimensional vector space $V$ and let $c_1,c_2ldots ,c_k$ be the distinct eigenvalues of T. Let $W_i$ be the null space of $(T-c_i I)$. If $T$ is diagonalizable, then prove that $$sum_i dim(W_i) = dim(V)$$




I am unable to connect things in order to logically think about this. How do I go about proving this?










share|cite|improve this question











$endgroup$





Let $T$ be a linear operator on a finite dimensional vector space $V$ and let $c_1,c_2ldots ,c_k$ be the distinct eigenvalues of T. Let $W_i$ be the null space of $(T-c_i I)$. If $T$ is diagonalizable, then prove that $$sum_i dim(W_i) = dim(V)$$




I am unable to connect things in order to logically think about this. How do I go about proving this?







linear-algebra vector-spaces linear-transformations






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edited Jan 29 at 7:17









Chinnapparaj R

5,8602928




5,8602928










asked Jan 29 at 7:13









AbhayAbhay

3789




3789












  • $begingroup$
    See proposition $5.21$ on page no:$101$ in this book!
    $endgroup$
    – Chinnapparaj R
    Jan 29 at 7:36




















  • $begingroup$
    See proposition $5.21$ on page no:$101$ in this book!
    $endgroup$
    – Chinnapparaj R
    Jan 29 at 7:36


















$begingroup$
See proposition $5.21$ on page no:$101$ in this book!
$endgroup$
– Chinnapparaj R
Jan 29 at 7:36






$begingroup$
See proposition $5.21$ on page no:$101$ in this book!
$endgroup$
– Chinnapparaj R
Jan 29 at 7:36












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Since $T$ is similar to a diagonal matrix, there exists a basis $mathfrak{B}={v_j}_{jle dim V}$ of $V$ such that for each $j$, $v_j in W_k =ker (T-c_kI)$ for some $k$. Since $mathfrak{B} subset bigoplus_k W_k$, it follows
$$
V =text{span} mathfrak{B} =bigoplus_k W_k
$$
and $dim V =dim bigoplus_k W_k=sum_k dim W_k.$






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    $begingroup$

    Since $T$ is similar to a diagonal matrix, there exists a basis $mathfrak{B}={v_j}_{jle dim V}$ of $V$ such that for each $j$, $v_j in W_k =ker (T-c_kI)$ for some $k$. Since $mathfrak{B} subset bigoplus_k W_k$, it follows
    $$
    V =text{span} mathfrak{B} =bigoplus_k W_k
    $$
    and $dim V =dim bigoplus_k W_k=sum_k dim W_k.$






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      0












      $begingroup$

      Since $T$ is similar to a diagonal matrix, there exists a basis $mathfrak{B}={v_j}_{jle dim V}$ of $V$ such that for each $j$, $v_j in W_k =ker (T-c_kI)$ for some $k$. Since $mathfrak{B} subset bigoplus_k W_k$, it follows
      $$
      V =text{span} mathfrak{B} =bigoplus_k W_k
      $$
      and $dim V =dim bigoplus_k W_k=sum_k dim W_k.$






      share|cite|improve this answer









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        $begingroup$

        Since $T$ is similar to a diagonal matrix, there exists a basis $mathfrak{B}={v_j}_{jle dim V}$ of $V$ such that for each $j$, $v_j in W_k =ker (T-c_kI)$ for some $k$. Since $mathfrak{B} subset bigoplus_k W_k$, it follows
        $$
        V =text{span} mathfrak{B} =bigoplus_k W_k
        $$
        and $dim V =dim bigoplus_k W_k=sum_k dim W_k.$






        share|cite|improve this answer









        $endgroup$



        Since $T$ is similar to a diagonal matrix, there exists a basis $mathfrak{B}={v_j}_{jle dim V}$ of $V$ such that for each $j$, $v_j in W_k =ker (T-c_kI)$ for some $k$. Since $mathfrak{B} subset bigoplus_k W_k$, it follows
        $$
        V =text{span} mathfrak{B} =bigoplus_k W_k
        $$
        and $dim V =dim bigoplus_k W_k=sum_k dim W_k.$







        share|cite|improve this answer












        share|cite|improve this answer



        share|cite|improve this answer










        answered Jan 29 at 7:35









        SongSong

        18.5k21651




        18.5k21651






























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